Modelling and characterisation of antennas and propagation for body-centric wireless communication

PhDBody-Centric Wireless Communication (BCWC) is a central point in the development of fourth generation mobile communications. The continuous miniaturisation of sensors, in addition to the advancement in wearable electronics, embedded software, digital signal processing and biomedical technologies, have led to a new concept of usercentric networks, where devices can be carried in the user’s pockets, attached to the user’s body or even implanted. Body-centric wireless networks take their place within the personal area networks, body area networks and body sensor networks which are all emerging technologies that have a broad range of applications such as healthcare and personal entertainment. The major difference between BCWC and conventional wireless systems is the radio channel over which the communication takes place. The human body is a hostile environment from radio propagation perspective and it is therefore important to understand and characterise the effect of the human body on the antenna elements, the radio channel parameters and hence the system performance. This is presented and highlighted in the thesis through a combination of experimental and electromagnetic numerical investigations, with a particular emphasis to the numerical analysis based on the finite-difference time-domain technique. The presented research work encapsulates the characteristics of the narrowband (2.4 GHz) and ultra wide-band (3-10 GHz) on-body radio channels with respect to different digital phantoms, body postures, and antenna types hence highlighting the effect of subject-specific modelling, static and dynamic environments and antenna performance on the overall body-centric network. The investigations covered extend further to include in-body communications where the radio channel for telemetry with medical implants is also analysed by considering the effect of different digital phantoms on the radio channel characteristics. The study supports the significance of developing powerful and reliable numerical modelling to be used in conjunction with measurement campaigns for a comprehensive understanding of the radio channel in body-centric wireless communication. It also emphasises the importance of considering subject-specific electromagnetic modelling to provide a reliable prediction of the network performance

Book of Abstracts 15th International Symposium on Computer Methods in Biomechanics and Biomedical Engineering and 3rd Conference on Imaging and Visualization

In this edition, the two events will run together as a single conference, highlighting the strong connection with the Taylor & Francis journals: Computer Methods in Biomechanics and Biomedical Engineering (John Middleton and Christopher Jacobs, Eds.) and Computer Methods in Biomechanics and Biomedical Engineering: Imaging and Visualization (JoãoManuel R.S. Tavares, Ed.). The conference has become a major international meeting on computational biomechanics, imaging andvisualization. In this edition, the main program includes 212 presentations. In addition, sixteen renowned researchers will give plenary keynotes, addressing current challenges in computational biomechanics and biomedical imaging. In Lisbon, for the first time, a session dedicated to award the winner of the Best Paper in CMBBE Journal will take place. We believe that CMBBE2018 will have a strong impact on the development of computational biomechanics and biomedical imaging and visualization, identifying emerging areas of research and promoting the collaboration and networking between participants. This impact is evidenced through the well-known research groups, commercial companies and scientific organizations, who continue to support and sponsor the CMBBE meeting series. In fact, the conference is enriched with five workshops on specific scientific topics and commercial software.info:eu-repo/semantics/draf

Development of Human Body CAD Models and Related Mesh Processing Algorithms with Applications in Bioelectromagnetics

Simulation of the electromagnetic response of the human body relies heavily upon efficient computational CAD models or phantoms. The Visible Human Project (VHP)-Female v. 3.1 - a new platform-independent full-body electromagnetic computational model is revealed. This is a part of a significant international initiative to develop powerful computational models representing the human body. This model’s unique feature is full compatibility both with MATLAB and specialized FEM computational software packages such as ANSYS HFSS/Maxwell 3D and CST MWS. Various mesh processing algorithms such as automatic intersection resolver, Boolean operation on meshes, etc. used for the development of the Visible Human Project (VHP)-Female are presented. The VHP - Female CAD Model is applied to two specific low frequency applications: Transcranial Magnetic Stimulation (TMS) and Transcranial Direct Current Stimulation (tDCS). TMS and tDCS are increasingly used as diagnostic and therapeutic tools for numerous neuropsychiatric disorders. The development of a CAD model based on an existing voxel model of a Japanese pregnant woman is also presented. TMS for treatment of depression is an appealing alternative to drugs which are teratogenic for pregnant women. This CAD model was used to study fetal wellbeing during induced peak currents by TMS in two possible scenarios: (i) pregnant woman as a patient; and (ii) pregnant woman as an operator. An insight into future work and potential areas of research such as a deformable phantom, implants, and RF applications will be presented

Smart Sensors for Healthcare and Medical Applications

This book focuses on new sensing technologies, measurement techniques, and their applications in medicine and healthcare. Specifically, the book briefly describes the potential of smart sensors in the aforementioned applications, collecting 24 articles selected and published in the Special Issue “Smart Sensors for Healthcare and Medical Applications”. We proposed this topic, being aware of the pivotal role that smart sensors can play in the improvement of healthcare services in both acute and chronic conditions as well as in prevention for a healthy life and active aging. The articles selected in this book cover a variety of topics related to the design, validation, and application of smart sensors to healthcare

Kinanthropometry IX

This is an edited collection of peer-reviewed papers presented at the Ninth International Conference of the Society for the Advancement of Kinanthropometry. Defined as the relationship between human body structure and function, kinanthropometry is an area of growing interest, and these proceedings will be of use to students, academics and professionals in the areas of ergonomics, sports science, nutrition, health, and other allied fields. The assembled works represent the latest research findings across kinanthropometry, moving the discipline forward and promoting good practice and the exchange of expertise

Kinanthropometry IX

This is an edited collection of peer-reviewed papers presented at the Ninth International Conference of the Society for the Advancement of Kinanthropometry. Defined as the relationship between human body structure and function, kinanthropometry is an area of growing interest, and these proceedings will be of use to students, academics and professionals in the areas of ergonomics, sports science, nutrition, health, and other allied fields. The assembled works represent the latest research findings across kinanthropometry, moving the discipline forward and promoting good practice and the exchange of expertise

Body composition in athletes : from methodology to application

Doutoramento em Motricidade Humana na especialidade de Actividade Física e SaúdeIt is recognized that an accurate body composition assessment is relevant for prescribing adequate training and nutritional regimens in highly trained athletes. The present dissertation presents four research studies conducted under the scope of the body composition methodological and alteration research areas. In the methodological area, an alternative solution to evaluate participants taller than the DXA scan area was valid and simple to be used in athletes engaged in sports recognised for including very tall competitors. Another study was performed to test the validity of a combined motion sensor (accelerometer and heart rate monitor) in assessing total and activity energy expenditure of highly trained athletes. Using doubly labelled water as the reference method, the combined sensor was accurate for estimating energy expenditure at a group level but was of limited validity for assessing energy requirements in athletes. Under the scope of the research area on body composition alterations, a very detailed characterization of body composition changes at the molecular, cellular, tissue, and whole-body level of analysis in elite junior basketball players during the course of a season was studied. The season was associated with an improved body composition profile, particularly in males. Considering the relevance of an accurate body composition and energy balance regulation over the season, a last study was conducted to provide reference percentiles (5th, 25th, 50th, 75th, and 95th) for several anthropometric and DXA body composition variables, stratified by sex and sport. These reference percentiles should be a helpful tool for coaches and nutritionists, in both laboratory and field settings, to prescribe exercise training and dietary intake regimens that assure an adequate energy requirement regulation in athletic populations over the season.É reconhecida a relevância de uma avaliação válida da composição corporal para a prescrição adequada de programas de treino e dieta alimentar em atletas de alta competição. Esta dissertação apresenta quatro trabalhos de investigação conduzidos no âmbito de duas grandes áreas de investigação da composição corporal, metodologia e alterações. No âmbito da área metodológica foi avaliada uma alternativa para determinar a composição corporal em atletas cuja estatura excede a área de scan da DXA. Esta solução mostrou-se válida e simples para avaliar atletas muito altos, normalmente envolvidos em desportos onde esta característica apresenta uma vantagem competitiva. Foi realizado um outro estudo para testar a validade de um sensor de movimento que combina acelerometria e cardiofrequencímetro na avaliação do dispêndio energético total e em atividade física de atletas de alta competição. Tendo como referência a técnica da água duplamente marcada, o sensor combinado apresentou-se como um método válido na estimação do dispêndio energético num grupo de atletas, embora na avaliação das necessidades energéticas individuais este equipamento tenha apresentado uma validade muito limitada. No âmbito da área de investigação das alterações da composição corporal foi conduzido um estudo que caracterizou de forma muito detalhada as alterações da composição corporal ao nível molecular, celular, tecidular e de corpo inteiro em jogadores de basquetebol ao longo de uma época desportiva. Foi observada uma associação entre a época desportiva e a melhoria do perfil de composição corporal, de forma mais notória nos basquetebolistas do sexo masculino. Dada a relevância de uma avaliação válida da composição corporal assim como da regulação do balanço energético ao longo de uma época desportiva, foi conduzido um último estudo que estabelece percentis de referência (percentis 5, 25, 50, 75 e 95) para diversas variáveis obtidas através de técnicas antropométricas e pela DXA, em função do género e desporto. Estes percentis de referência podem ser instrumentos muito úteis para treinadores e nutricionistas, quer a nível laboratorial como não laboratorial, de forma a prescrever um regime de treino e dieta alimentar que garanta o equilíbrio das necessidades energéticas da população atlética ao longo de uma época desportiva.FCT - Fundação para a Ciência e a Tecnologi

Computational Analysis and Methods for Electromagnetic Exposure Limits, Antenna Optimization and Cell Phone Design

In recent years, the advancements of wireless technologies have led to rapid developments in the field of telecommunication, power delivery and bio-medical applications. During the evolution of a wireless technology, the electromagnetic compatibility (EMC) between a radiating source (e.g., an antenna) and nearby active or passive elements (e.g., a closely integrated electronic component or a human body) often introduces challenging design requirements. This thesis focuses on the applications of state-of-the-art computational electromagnetic compatibility (CEMC) techniques in multidisciplinary engineering design tasks, with an emphasis on computational bio-electromagnetic compatibility (CBEMC). The analyses reported in this thesis span practical applications from power frequency (Hz) to radio frequency (GHz), providing research outcomes which significantly benefit the understandings of low-frequency human body exposure safety and radio-frequency antenna integration and optimization. The research aspect of the thesis is initiated with a thorough review of the existing low-frequency exposure safety guidelines recommended by international regulatory committees. The subsequent analyses suggest essential scientific basis for the update and revision of the existing exposure limits. Practical exposure scenarios (e.g., magnetic resonant wireless power transfer) are investigated with novel assessment techniques. Subsequently, a computer-aided optimization scheme based on network-distributed genetic algorithms is applied to highly detailed numerical mobile phone model and human body phantoms. The investigated optimization technique is proven to be superior than traditional empirical approaches. Finally, the CEMC techniques are applied in the context of non-dosimetry related engineering design environment by investigating the integration of a miniature loudspeaker (acoustic component) and a mobile device antenna (radio frequency component). Based on simulation and measurement data, the coupling mechanisms are determined to establish the fundamental design guidelines for optimum antenna-speaker co-existence and performance. In summary, this thesis details several novel applications of CEMC in the most stringent and complex industrial design environments. The presented research findings serve as indispensable basis for future research oriented towards the exposure-compliant and electromagnetic- compatible designs for novel wireless technologies